Process for manufacturing sheet metal



- 1,621,380 March 15, 1927. w. E- RUDER PROCESS FOR MANUFACTURING SHEET METAL Filed May 28; 1924 Fi l. 9 l0 13 a 9 a 4 2 I5 rF h g 7' lmvemtar'i William E.Ruder'-,

' 'byM His Attorney' Patented Mar. 15, 1927.

UNITED STATES PATENT! OFFICE.

WILLIAM E. RUDER, or scnnnnc'mmr, NEW YORK, ASSIGNOR T emmnu' ntnorarc come-ANY, A CORPORATION or mew YORK.

PROCESS FOR MANUFACTURING SHEET METAL.

Application filed Kay 28,

The present invention relates to the manufacture of sheet material and particularly to the roduction of sheet steel suitable for use in e ectric apparatus for the construction of magnetic cores.

' It has been the practice heretofore in the manufacture of sheet metal to 7 cast the molten metal into the form of large ingots which are converted byia rolling mill into an 10 elongated bar of smaller cross-section. This bar is cut into lengths known as sheet bars which are of a size suitable for rolling intowas most pronounced. Usually a portion of the remainder of the ingot which was rolled down to sheet form contained some cavities which caused a laminated structure in the sheet metal made therefrom.

Instead of casting large ingotsv requiring an expensive-rolling operation in order to produce bars suitable for rolling into sheets and entailing the removal' of defective metal, I have provided in accordance with my present invention a new process whereby the 400 to 500 revolutions per minute, the mold molten metal is cast into the form ofa hollow cylinder in a mold rotatable at high speed so as to' distribute the metal by'centrlfu al force. The resulting cast cylinder is I su divided into bars suitable for rolling into sheets. This process therefore entirely eliminates the difficulties due to the formation of a cavity or cavities in the casting and eliminates the rolling operation formerly required to convert the large ingotsinto bars from which sheets can be rolled. M invention will be described in greater detail in the following specification taken in connection with the accompanying drawing, in which Fi lis an elevation partly in section of the casting apparatus, Fig. 2 is an end view partly in section of the casting mold,

Fig.- .3 is a perspective view of a casting produced in accordance with my invention 192 4. Serial No. 716,522.

broken apart quent rolling.

As shown in bars suitable for subsestandards 5, 6. The mold is rotated b any suitable sorts of power =belted to a pul ey 7.

The casting device comprises a cylindrical mold 8 preferably consisting of cast iron.- This mold is connected by bolts or other suit able means to a frame 9. which is mounted upon the shaft 2. Surrounding the mold 8 is an enclosing shell 10 which is separated from they container 8 b a layer 11 of heat insulating material. urroundin the rotatable mold is a protective shiel 12. Removably bolted to the rim of the outer shell 10 of the mold is an annular rim plate13 which serves as an end wall to hold the molten metal when .it is distributed by centrifugal action against the interior wall of the rotating mold.

Fig. 1 the casting cylinder 1, in which castings are made is supported upon a horizontal shaft 2 which is rotatably mounted upon bearings 3 and 4, mounted on As shown in the drawing the molten metal is supplied to the mold by a ladle 14 which 'is mounted by a horizontal shaft '15 upon a wheeled truck 16. By means of this ladle the molten metal may be carried from the melting furnace to the mold. By tilting the ladle through rotation of the shaft. 15,

the molten charge is introduced into" the" mold 1.

The mold 1 is rotated at a speed of about being brought up to speed before the molten charge is introduced. -The molten metal is spread outby centrifugal force as a layer of uniform thickness upon the interior surface of the mold. The. centrifugal force causes impurities, such as slag'or gases to separate from the heavier metal and to segregate upon the interior surface. The

thickness of the casting may vary widely.

the surface of the cylindrical casting as in-- where the cross section of the metal is reduced, are convenient for subdividing the cast cylinder into longitudinal segments, particularly when the cast metal co'nsistsof silicon steel which is relatively brittle. In that case the indented cylindrical casting can be broken by properly applied blows into a number of segments as indicated in Fig. 4. Instead of breaking up the cylinder asdescribed, it may be subdivided by shearing or cutting, preferably while the casting is hot.

The segments 20 shown in Fig. 4 as being piled against each other are slightly curved, substantially rectangular plates which can be directly fed in the rolling mill and converted into sheets. In the rolling process impurities on the surface of the bars 20 will be separated from the sheet as scale.

Although I have referred particularly to the production of silicon 'steel sheets, my

process may be applied to the production of sheet metal of any character.

What I claim as new and desire to secure by Letters Patent of the United States, is:

The method of manufacturing metal blanks preliminary to rolling into sheets which consists in casting molten metal into cylindrical form having a plurality of longitudinal grooves, and fracturing the metal in line with said grooves to separate said cylinder into a plurality of segments.

In witness whereof, I have hereunto set my hand.

WILLIAM E. RUDER. 

